Principal officials did not cite a reason for the swap in subadvisors. Nor did the filing reveal the size of the mandate. Principal's website lists the fund with $1.017 billion in AUM and Causeway Capital Markets is also a subadvisor on the fund.

A Principal spokesperson was not immediately available for comment.

Barrow Hanley will fallow a value-based approach to stock seelction for the fund, aiming to generate alpha primarily through stock selection and through the resulting sector, region and country allocation. David Hodges and Randolph Wrighton, Jr. will be the PMs for Barrow Hanley on the mandate.

The fund will pay Barrow Hanley the same fee it currently pays Causeway Capital.

For Axa Rosenberg the loss is not the first since it confessed that a programming mistake caused it to run into issues selecting investments for its portfolios in June of 2009. The error was fixed between last September and November last year. However, Charles Schwab reacted to the issue by liquidating its four Laudus Funds subadvised by Axa Rosenberg at the end of last month.

Co-founder Barr Rosenberg took a leave of absence in May and then resigned from the firm's board at the start of June when he and co-founder Kenneth Reid sold their remaining 25 percent stake in the firm in June to Axa Investment Managers.

Separately, Bloomberg reported in April that Vanguard was reviewing Axa Rosenberg's role on a $1 billion subadvisor mandate on its Vanguard Explorer Fund, a $525 mandate on the Vanguard U.S. Value Fund and a $71 million mandate on the Vanguard Market Neutral Fund.&nbsp